(AP Photo/Mark J. Terrill)

(CNN)Beyoncé and Jay Z have welcomed twins, a source close to the couple tells CNN.

There was no immediate word on the gender of the babies or their names.

The superstar singer and her mogul husband, who married in 2008, are also parents to a five-year-old daughter, Blue Ivy.

Queen Bey announced her pregnancy in February on Instagram.

"We would like to share our love and happiness. We have been blessed two times over. We are incredibly grateful that our family will be growing by two, and we thank you for your well wishes. The Carters, " she posted.

According to the March of Dimes, close to 60 percent of all twins and more than 90 percent of triplets are born prematurely (before 37 weeks). The average twin pregnancy lasts 35 weeks. Early births can lead to longer hospital stays in order for doctors to monitor the infants lungs and other organs, give babies time to gain weight and treat them for any existing conditions related to being premature.

Beyoncé's father, Mathew Knowles, tweeted, "They're here! #beyonce #twins #jayz #happybirthday" with a photo of balloons that said, "Happy Birthday to the twins! Love, Granddad."

View image on Twitter

Mathew Knowles @MathewKnowles

They're here!  

9:11 AM - 18 Jun 2017

He was predictably dragged by Twitter for announcing their arrival before Beyonce did.